Firstly, I created a form.php. Secondly I connected to http://192.168.1.16/form.php, it shows:
Then, I input “Larry” and press Return. It then shows:
Exercise 7
April 9, 2008Exercise 6
April 9, 20081. I set up the test environment as follows:
PHP Server: Fedora 1, Apache, PHP4, IP address=192.168.1.16
Client: Windows XP, IP address=192.168.1.9
For $REMOTE_ADDR
When I connected to server from client, it showed:
For $SERVER_NAME
When I connected to server from client, it showed
For $PHP_SELF
When I connected to server from client, it showed:
2. When I connected to http://192.168.1.16/hello_world.php, it showed:
Exercise 5
April 9, 20081. A simple chat client/server system can handle multiple users by using
the socket and multithread.
First, a specific port in server is assigned to listen to the client who wants to connect to. Then, client connects to this listening port and provides its ip address with local port number to the server. And server creates an array to hold this unique connection information for each connected client. Therefore, server is able to accept more than one connection.
In addition to using socket, chat system is also using multithread to improve the performance. In general, they use two threads: one for sending out the message and the other for read a message from server. Therefore, each client can read and send the message simultaneously.
2. Other than client/server architecture, in recent, a newer distributed network architectures, Peer to Peer (P2P) and Grid computing, are evolved in which a number of computers are connected each other forming a bigger network. They share resources like storage space, bandwidth and processing power within the network. On the network, no computer is dedicated to serve other nodes. All of them are equal peer nodes which act as both client and server simultaneously. It results in increasing the robustness of system in case of any system failure.
However, there are some distinguishing properties between P2P and Grid. First, grid computing does request particular unique software to achieve the computing project. Second, grid computing focuses on solving problems too intensive for any stand alone computer while P2P is commonly used for file sharing, media streaming, instant messaging or discussion forum.
In conventional client/server architecture, client inputs data to and receives result from application on given server. Then application will store the data in a database. It is illustrated in figure 5.2.1. Therefore, either data or transaction is able to be preserved. Data integrity is an important rule for any system. However, in the P2P/Grid network architecture, the data component can be moved anywhere at anytime. It is illustrated in figure 5.2.2. In this way, the workflow and services –oriented applications have to be changed as follows:
- Mobility of objects, transactions, applications and data storage.
- Referential integrity of all data regardless of its state or location.
- Capability of supporting multiple instances of each component.
- Capability of supporting failover and recovery of any component.
- Capability of coping with multiple data acquisitions from different devices.
- Capability of coping with scaling up of system.
Figure 5.2.1 Client-Server Architecture
Figure 5.2.2 Distributed Computing Architecture
Reference:
A comparison of distributed and Peer-to-peer computing architectures.
Retrieved 4 April 2008 from:
Beal, VA (2005). All about Peer-to-Peer. Retrieved 3 April 2008 from:
http://www.webopedia.com/DidYouKnow/Internet/2005/peer_to_peer.asp
Grid computing. Retrieved 3 April 4, 2008 from:
http://www.webopedia.com/TERM/g/grid_computing.html
3. Ruby on Rails and Turbo Gears have the similarities and dissimilarities:
They have the following similarities:
i. Both frameworks are using push MVC (Model-View-Controller) architecture.
ii. Both of them are supporting AJAX (Asynchronous JavaScript and XML)
iii. Both of them are security frameworks, template frameworks and form validation frameworks.
They also have the following differences:
i. Ruby on Rails is written by Ruby while Turbo Gears is written by Python.
ii. Ruby on Rails is DB migration frameworks and caching frameworks while Turbo Gears is not.
Reference:
Comparison of web application frameworks. Retrieved 4 April 2008 from:
http://en.wikipedia.org/wiki/Comparison_of_web_application_frameworks
Exercise 4
April 9, 2008Exercise 4
1. IP, Internet Protocol, is a data-oriented protocol used for communicating data across a network. It is a network layer protocol and is encapsulated in data link layer protocol. It also provides different services, like addressing, fragmentation, packet timeout and prioritization of labeled packets.
DNS, Domain Name System, is an Internet service which translates domain names into IP address because domain name is easier to remember while Internet is working based on IP address.
2. TCP, Transmission Control Protocol, is one of major protocol in TCP/IP network. It makes two hosts to establish connection and exchange data streams. Furthermore, it provides a reliable, in-order delivery of packets during transmission.
During data transmission, IP provides the instruction how the packet from sending host to receiving host while TCP provide the assurance of packets received by receiving host.
3. Intranet is a private network that uses Internet protocol and network connectivity which aims at share information within organization in secure way.
e.g http://intranet.kerrylogistics.com/
Extranet is also a private network that use Internet protocol and network connectivity which setup between organizations. So that they can share or exchange information in relative secure way.
Web portal is a site which provides a single function. As usual, it functions as a point of access to information on the Internet.
B2B- business to business, is a common term describing electronic transaction between companies.
B2C – business to customer, is a common term describing electronic transaction between company and customer.
VPN is a secure communication tunnels over Internet between two specific network.
4. VPN is a secure communication tunnels over Internet between two specific networks. In B2B e-commerce, it is cheaper way for enterprises to exchange application data.
Exercise 3
April 9, 2008Exercise 3
Followings are the basic steps to develop web application with Rapid Evolutionary Prototyping Approach.
1. Produce information material start with needs defined from end-users.
2. Assess, analyze and select needs based on systematic review and multidisciplinary teams
3. Identify solutions, set the goals and analyze tasks.
4. Design interface, design solution and produce prototype
5. End-users test and feedback
6. Further improve the prototype in according to users’ comment until a final product released.
7. Implement a solution.
Exercise 2
April 9, 20081. Ebay, http://www.ebay.com
- Online shopping: It is a popular online shopping and auction website. It provides a variety of goods for buyers.
- Electronic payment: It offers an electronic payment in her website, such as PayPal.
- Database access: It allows buyers to browse or search all items under each category.
- WAP site: http://m.ebay.com/
-
2. Sonyericsson, http://www.sonyericsson.com
- Online shopping: It allows to download themes or ringtones, games, softwares and images with charge.
- Electronic payment: It offers an electronic payment in the web site, such as Visa, Master and PayPal
- Database access: It allows users to browse or search different mobile phones, themes, ringtones and etc..
- WAP site: It has WAP site for mobile phone users to download mobile phone instruction.
3. O2, http://www.o2.co.uk
- Online shopping: It provides mobile phone and mobile phone service plans.
- Electronic payment: It offers an electronic payment in the web site, such as Visa & Master.
- Database access: It allows users to download the mobile phones manuals.
- WAP site: http://mywap.o2.co.uk
4. Smartone, http://www.smartone-vodafone.com
- Online shopping: It provides mobile phone services.
- Electronic payment: It offers a system named “Ezpay” for user to settle payment in store-valued method.
- Database access: It allows users to browse the mobile phones and tariff plans.
- WAP site: http://wap.smartone.com.hk
5. T-Mobile, http://www.t-mobile
- Online shopping: It sells mobile phones, mobile broadband and mobile phone services.
- Electronic payment: It allows the payment by Visa or sms.
- Database access: It allows to browse different models of mobile phone or download pictures, movies, ringtones and games.
- WAP site: http://wap.t-mobile.co.uk
Exercise 1
April 9, 20081a. An online community means a group of people who primarily interact via computer network such as Internet. And e-commerce is usually used to describe the retailing activities which uses the Internet (online retailing). Therefore, size of online community increases, the success rate of online retailing will increase.
1bi. Their interface and framework design are similar but they have a local community sense in auction.
1bii. The electronic payment systems they are supporting are PayPal, Escrow and Credit Card. All these payment systems are globally acceptable.
1biii. By using online auction, different parties have their benefits:
For buyers - can bid the items they wanted any place and any time.
- can buy the goods worldwide, not limited to local.
- can compare the goods easily.
For sellers - can sell the goods to worldwide.
- can sell the goods any place and any time.
For owners - can make money for each transaction.
1c. Online job hunter, online bookstore and e-banking are examples of an online business using online community approach.
2a. It provides a variety of choices of goods and clear framework which make buyers to choose goods they wanted easily.
Select a book you want. Next, add the shopping list and then add to shopping cart. Lastly, sign on with your account and then settle payment.
2b. No
2c. Book, Movie, Music, Game, Digital downloads, electronics, computer, home & garden, grocery, toys, kids & baby, apparel, shoes & jewelry, health & beauty, sports & outdoor and tools, auto & industrial
3. This is the website which aims at comparing different online shopping sites and provide this information to buyers.
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